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Bone marrow-derived mesenchymal stem cell-derived exosomeloaded miR-129-5p targets high-mobility group box 1 attenuates neurological-impairment after diabetic cerebral hemorrhage 被引量:2
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作者 Yue-Ying Wang Ke Li +5 位作者 Jia-Jun Wang Wei Hua Qi Liu Yu-Lan Sun Ji-Ping Qi Yue-Jia Song 《World Journal of Diabetes》 SCIE 2024年第9期1979-2001,共23页
BACKGROUND Diabetic intracerebral hemorrhage(ICH)is a serious complication of diabetes.The role and mechanism of bone marrow mesenchymal stem cell(BMSC)-derived exosomes(BMSC-exo)in neuroinflammation post-ICH in patie... BACKGROUND Diabetic intracerebral hemorrhage(ICH)is a serious complication of diabetes.The role and mechanism of bone marrow mesenchymal stem cell(BMSC)-derived exosomes(BMSC-exo)in neuroinflammation post-ICH in patients with diabetes are unknown.In this study,we investigated the regulation of BMSC-exo on hyperglycemia-induced neuroinflammation.AIM To study the mechanism of BMSC-exo on nerve function damage after diabetes complicated with cerebral hemorrhage.METHODS BMSC-exo were isolated from mouse BMSC media.This was followed by transfection with microRNA-129-5p(miR-129-5p).BMSC-exo or miR-129-5poverexpressing BMSC-exo were intravitreally injected into a diabetes mouse model with ICH for in vivo analyses and were cocultured with high glucoseaffected BV2 cells for in vitro analyses.The dual luciferase test and RNA immunoprecipitation test verified the targeted binding relationship between miR-129-5p and high-mobility group box 1(HMGB1).Quantitative polymerase chain reaction,western blotting,and enzyme-linked immunosorbent assay were conducted to assess the levels of some inflammation factors,such as HMGB1,interleukin 6,interleukin 1β,toll-like receptor 4,and tumor necrosis factorα.Brain water content,neural function deficit score,and Evans blue were used to measure the neural function of mice.RESULTS Our findings indicated that BMSC-exo can promote neuroinflammation and functional recovery.MicroRNA chip analysis of BMSC-exo identified miR-129-5p as the specific microRNA with a protective role in neuroinflammation.Overexpression of miR-129-5p in BMSC-exo reduced the inflammatory response and neurological impairment in comorbid diabetes and ICH cases.Furthermore,we found that miR-129-5p had a targeted binding relationship with HMGB1 mRNA.CONCLUSION We demonstrated that BMSC-exo can reduce the inflammatory response after ICH with diabetes,thereby improving the neurological function of the brain. 展开更多
关键词 Bone marrow mesenchymal stem cells Exosome Diabetic cerebral hemorrhage Neuroinflammation MicroRNA-129-5p High mobility group box 1
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Formal Verification of Secrecy in Group Key Protocols Using Event-B
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作者 Amjad Gawanmeh Sofiène Tahar Leila Jemni Ben Ayed 《International Journal of Communications, Network and System Sciences》 2012年第3期165-177,共13页
Group key security protocols play an important role in today’s communication systems. Their verification, however, remains a great challenge because of the dynamic characteristics of group key construction and distri... Group key security protocols play an important role in today’s communication systems. Their verification, however, remains a great challenge because of the dynamic characteristics of group key construction and distribution protocols. Security properties that are well defined in normal two-party protocols have different meanings and different interpretations in group key distribution protocols, specifically, secrecy properties, such as group secrecy, forward secrecy, backward secrecy, and key independence. In this paper, we present a method to verify forward secrecy properties for group-oriented protocols. The method is based on a correct semantical link between group key protocols and event-B models and also uses the refinement process in the B method to model and verify group and forward secrecy. We use an event-B first-order theorem proving system to provide invariant checking for these secrecy properties. We illustrate our approach on the Tree based Group Diffie-Hellman protocol as case study. 展开更多
关键词 group KEY Protocols FORMAL Verification FORWARD SECRECY SECRECY event-B
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Analysis of platinum-group elements in drill core samples from the Meishan Permian-Triassic boundary section, China 被引量:2
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作者 XU Lin LIN Yangting 《Chinese Journal Of Geochemistry》 EI CAS CSCD 2014年第4期365-373,共9页
There is a long-standing controversy of what triggered the extinction at the Permian-Triassic boundary, the most severe mass extinction in the geologic record, including flood basaltic volcanism and/or bolide impact h... There is a long-standing controversy of what triggered the extinction at the Permian-Triassic boundary, the most severe mass extinction in the geologic record, including flood basaltic volcanism and/or bolide impact hypothesis. In order to clarify various pieces of evidence for the mass extinction event at the Permian-Triassic boundary, some researchers from some laboratories throughout the world have made a comprehensive study on a group of samples from the Meishan area of China. Some fresh core samples from the Permian-Triassic boundary in the Meishan area were analyzed in this study. The results showed that there is no Ir anomaly. Moreover, the PGEs patterns of those samples show obvious differentiation characteristics, that is different from the case encountered in meteorites. So no evidence supports the hypothesis of extraterrestrial impact. In contrast, the PGEs patterns are similar to those of Siberian and Emeishan basalts, which indicates that those PGEs are derived mainly from the basalts, lending a support to the correlation between mass extinction at the Permian-Triassic boundary and flood basaltic volcanism. This study has also confirmed the results for samples from section C prior to the analysis of the samples. 展开更多
关键词 界线剖面 铂族元素 岩芯样品 三叠系 元素分析 中国 峨眉山玄武岩 灭绝事件
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An Event Alarm System Based on Single and Group Human Behavior Analysis 被引量:1
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作者 Hung-Yu Yeh I-Cheng Chang Yung-Hsin Chen 《Journal of Electronic Science and Technology》 CAS CSCD 2017年第2期123-132,共10页
Due to the increasing demand for security, the development of intelligent surveillance systems has attracted considerable attention in recent years. This study aims to develop a system that is able to identify whether... Due to the increasing demand for security, the development of intelligent surveillance systems has attracted considerable attention in recent years. This study aims to develop a system that is able to identify whether or not the people need help in a public place. Different from previous work, our work considers not only the behaviors of the target person but also the interaction between him and nearby people. In the paper, we propose an event alarm system which can detect the human behaviors and recognize the happening event through integrating the results generated from the single and group behavior analysis. Several new effective features are proposed in the study. Besides, a mechanism capable of extracting one-to-one and multiple-to-one relations is also developed. Experimental results show that the proposed approach can correctly detect human behaviors and provide the alarm messages when emergency events occur. 展开更多
关键词 Index Terms event alarm system group behavior analysis human behavior recognition single behavior analysis stooping curve.
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El Nino and anti-El Nino events in 1854-1987 被引量:9
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作者 Zang Hengfan and Wang Shaowu National Marine Environmental Forecasting Center, State Oceanic Administration (SOA) , Beijing, China Department of Geophysics, Peking University, Beijing, China 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1990年第3期353-362,共10页
-Using the COADS data set of sea surface temperature in the Equatorial Eastern Pacific, thirty one El Nino events and twenty four anti -El Nino events were identified for the period from 1854 to 1987. The results were... -Using the COADS data set of sea surface temperature in the Equatorial Eastern Pacific, thirty one El Nino events and twenty four anti -El Nino events were identified for the period from 1854 to 1987. The results were compared with those of the other authors. The El Nino events (or anti -El Nino events ) are classified into two groups according to the timing of occrrence of the events: one starts at the first half of a year, another begins at the second half of a year. Both 1982-1983 and 1986-1987 events fall into the second group, which are characterized by the eastward migration of the positive anomaly of the sea surface temperature and the significant increasing of the anomaly in September or October. 展开更多
关键词 Nino EI El Nino and anti-El Nino events in 1854-1987
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Discovery of rhyolitic tuffaceous slate in the southwestern margin of Yangtze Craton:Zircon U-Pb ages(2491 Ma)and tectonic-thermal events 被引量:9
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作者 Jun-ping Liu Su-mei Tian +7 位作者 Xun-zao Zhu Jin-hua Ma Jing Li Shao-bin Hu Sai-ying Yu Hu Zhang Zhong-ming She Xu-gui Li 《China Geology》 2021年第4期616-629,共14页
The Mesoproterozoic Dongchuan Group that is widely exposed in Yimen area,central Yunnan Province is a series of sedimentary sort of low-grade metamorphic rocks interbedded with volcanic rocks,which are closely related... The Mesoproterozoic Dongchuan Group that is widely exposed in Yimen area,central Yunnan Province is a series of sedimentary sort of low-grade metamorphic rocks interbedded with volcanic rocks,which are closely related to the early tectonic evolution of the Earth.However,its formation era,sedimentary filling sequence,and geotectonic characteristics have always been in dispute.In this study,several rhyolitic tuffaceous slate interlayers with a centimeter-level thickness were found in the previously determined Heishan Formation of the Dongchuan Group located to the western part of Yimen-Luoci fault zone.This paper focuses on the study of the rhyolitic tuffaceous slate in Qifulangqing Village,Tongchang Township,Yimen County.LA-ICP-MS zircon dating was conducted,achieving the crystallization age of magma of 2491±15 Ma and the metamorphic ages of about 2.3 Ga,2.0 Ga,and 1.8 Ga for the first time.Meanwhile,according to in-situ Hf isotope analysis,the zirconεHf(t)values were determined to range from−3.0 to 7.6,with an average of 2.7.Furthermore,the first-stage Hf model age(TDM1)was determined to be 2513−2916 Ma,indicating that the provenance of the rhyolitic tuffaceous slate is the depleted mantle or juvenile crust between the Middle Mesoarchean and the Late Neoarchean.Therefore,it is believed that the strata of the slate were deposited in the Late Neoarchean,instead of the Mesoproterozoic as determined by previous researchers.Accordingly,it is not appropriate to group the strata into the Mesoproterozoic Dongchuan Group.Instead,they should be classified as the Maolu Formation of the Neoarchean Puduhe Group given the lithologic association and regional information.Furthermore,the magma ages of 2491±15 Ma are highly consistent with the eras of the large-scale Late Neoarchean orogenic magmatic activities on the northern margin of the Yangtze Craton,and thus reflect the orogenic process consisting of subduction and collision from Late Neoarchean to Early Paleoproterozoic.The magmatic activities during this period were possibly caused by the convergence of the supercontinent Kenorland.Meanwhile,the metamorphic ages of 2.3 Ga,2.0 Ga,and 1.8 Ga are highly consistent with three metamorphic ages of 2.36 Ga,1.95 Ga,and 1.85 Ga of the northern margin of the Yangtze Craton,indicating that the strata experienced Paleoproterozoic tectonic-thermal events.The study area is located on the eastern margin of Qinghai-Tibet Plateau,and thus was possibly re-transformed by magmatism subjected to the subduction of the Meso-Tethys Ocean during the Early Cretaceous.The discoveries made in this study will provide strong petrological and chronological evidence for analyzing the early crustal evolution of the Yangtze block. 展开更多
关键词 Maolu Formation Puduhe group Late Neoarchean Zircon U-Pb age Tectonic-thermal event Geological survey engineering Eastern margin of Qinghai-Tibet Plateau Yangtze Craton
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A Study on the Evolution of Mechanism of Infectious Disease Analysis Model of Event Using Micro-Blog Platform 被引量:1
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作者 Haiying Ma 《Social Networking》 2015年第3期96-102,共7页
After the occurrence of unexpected group events of network, the relevant opinion information will spread rapidly through micro-blog, and the negative public opinion information will aggravate the unexpected the group ... After the occurrence of unexpected group events of network, the relevant opinion information will spread rapidly through micro-blog, and the negative public opinion information will aggravate the unexpected the group events to upgrade and expand the scope of harm. It is difficult to deal. So public opinion control is very important. In this paper, we establish an influence model for spreading of public opinion based on SIR model. Through the political analysis, this paper finds that the network group events will subside, but the influence scope, time and ability of event cannot be ignored. As a result of this study, the corresponding strategies are put forward in this paper. 展开更多
关键词 Micro-Blog group events of Network PUBLIC OPINION Control SIR Model
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A Long Lasting and Extensive Drought Event over China in 1876-1878 被引量:2
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作者 De'er Zhang Youye Liang 《Advances in Climate Change Research》 SCIE 2010年第2期91-99,共9页
Between 1876 and 1878 a large-scale drought occurred in China. This is a major meteorological disaster and an extreme climate event despite the cold climate at the end of the Little Ice Age. In this paper the dynamic ... Between 1876 and 1878 a large-scale drought occurred in China. This is a major meteorological disaster and an extreme climate event despite the cold climate at the end of the Little Ice Age. In this paper the dynamic evolution of the occurrence and development of the drought is reproduced on the basis of historical literature records. These were used to calculate the yearly numbers of drought-hit counties and to determine the spatial distribution in addition with concomitant famine, locust plague and pestilence epidemic for each of the three years. The persistent drought disaster spread over 13 provinces with its center in Shaanxi, Henan and Shanxi provinces, where the continuous non-soaking rain period exceeded 340 days. Conclusively, it is more severe than the worst drought (1928-1930) in the 20th century. This drought disaster of 1876-1878 took place in the descending phase of the 11th sunspot activity period and the start of the 12th period. It also happened during a spell of frequent E1 Nino events and corresponds with an extremely strong E1 Nino. 展开更多
关键词 extreme climate event DROUGHT meteorological disaster 1876-1878
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Heinrich events recorded in a loess-paleosol sequence from Hexigten,Inner Mongolia 被引量:2
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作者 Ji-Ling Song Hong-Yan Sun +3 位作者 Ming-Zhong Tian Xu-Jiao Zhang Xue-Feng Wen Miao Sun 《Geoscience Frontiers》 SCIE CAS CSCD 2018年第2期431-439,共9页
We describe the last glaciation climatic history Marine Isotope Stage(MIS, 2-4) from 66.7 ka to 14.5 ka in Hexigten, northeast Inner Mongolia, North China. The climate of the region experienced frequent and significan... We describe the last glaciation climatic history Marine Isotope Stage(MIS, 2-4) from 66.7 ka to 14.5 ka in Hexigten, northeast Inner Mongolia, North China. The climate of the region experienced frequent and significant fluctuations between dry-cold and less dry-cold during the late MIS4. The climate was generally warm and humid during early MIS3(MIS3 c) and late MIS3(MIS3 a), whereas it was cold and dry in middle MIS3(MIS3 b) and during MIS2. In this study, the cold and dry conditions were correlated with a stronger East Asian winter monsoon and strong dune activity; whereas, warm and humid conditions were related to a stronger East Asian summer monsoon(EASM) and weak dune activity. This study establishes six distinct dry and cold intervals during the last glacial period(66.7-14.5 ka) based on optically stimulated luminescence data, multi-proxies record(magnetic susceptibility, grain size analysis, Rb/Sr, SiO2/TiO2) and chemical index of alteration(CIA). The last glacial period may be correlated with Heinrich events 1 to 6 which were further confirmed by comparison with the Hulu cave stalagmites and Greenland ice core records. It is concluded that the study area was substantially affected by the EASM, as compared with the loess-desert transition zone of the Chinese Loess Plateau, especially in MIS3 c and suggested that the East Asian monsoon played a pivotal role in the last glacial period climate and dune activity. 展开更多
关键词 Climate RECORD DUNE activity Inner Mongolia East Asian MONSOON Marine ISOTOPE stage 2-4 Heinrich events
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A New Characterization of Simple K_3-groups 被引量:1
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作者 王临红 《Northeastern Mathematical Journal》 CSCD 2001年第2期205-209,共5页
In this paper, We show that the simple K\-3-groups can be characterized by the orders of their maximal abelian subgroups. That is, we have Theorem Let G be a finite group and M a simple K \-3-group. Then ... In this paper, We show that the simple K\-3-groups can be characterized by the orders of their maximal abelian subgroups. That is, we have Theorem Let G be a finite group and M a simple K \-3-group. Then G is isomorphic to M if and only if the set of the orders of the maximal abelian subgoups of G is the same as that of M . 展开更多
关键词 finite group simple K\-3-group maximal abelian subgroup prime graph
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Video Events Recognition by Scene and Group Context
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作者 裴明涛 王亚菲 赵猛 《China Communications》 SCIE CSCD 2013年第11期165-171,共7页
The ability to recognise video events has become increasingly more popular owing to its extensive practical applications.Most events will occur in certain scene with certain people,and the scene context and group cont... The ability to recognise video events has become increasingly more popular owing to its extensive practical applications.Most events will occur in certain scene with certain people,and the scene context and group context provide important information for event recognition.In this paper,we present an algorithm to recognise video events in different scenes in which there are multiple agents.First,we recognise events for each agent based on Stochastic Context Sensitive Grammar(SCSG).Then we propose the model of a scene in order to infer the scene in which the events occur,and we use a co-occurrence matrix of events to represent the group context.Finally,the scene and group context are exploited to distinguish events having similar structures.Experimental results show that by adding the scene and group context,the performance of events recognition can be significantly improved. 展开更多
关键词 events recognition scene context group context
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MiR-142-3p Regulates ILC1s by Targeting HMGB1 via the NF-κB Pathway in a Mouse Model of Early Pregnancy Loss 被引量:1
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作者 Xiang-li PANG Jie LI +2 位作者 Jing WANG Si-si YAN Jing YANG 《Current Medical Science》 SCIE CAS 2024年第1期195-211,共17页
Objective Innate lymphoid cells(ILCs)are a class of newly discovered immunocytes.Group 1 ILCs(ILC1s)are identified in the decidua of humans and mice.High mobility group box 1(HMGB1)is predicted to be one of the target... Objective Innate lymphoid cells(ILCs)are a class of newly discovered immunocytes.Group 1 ILCs(ILC1s)are identified in the decidua of humans and mice.High mobility group box 1(HMGB1)is predicted to be one of the target genes of miR-142-3p,which is closely related to pregnancy-related diseases.Furthermore,miR-142-3p and HMGB1 are involved in regulating the NF-κB signaling pathway.This study aimed to examine the regulatory effect of miR-142-3p on ILC1s and the underlying mechanism involving HMGB1 and the NF-κB signaling pathway.Methods Mouse models of normal pregnancy and abortion were constructed,and the alterations of ILC1s,miR-142-3p,ILC1 transcription factor(T-bet),and pro-inflammatory cytokines of ILC1s(TNF-α,IFN-γand IL-2)were detected in mice from different groups.The targeting regulation of HMGB1 by miR-142-3p in ILC1s,and the expression of HMGB1 in normal pregnant mice and abortive mice were investigated.In addition,the regulatory effects of miR-142-3p and HMGB1 on ILC1s were detected in vitro by CCK-8,Annexin-V/PI,ELISA,and RT-PCR,respectively.Furthermore,changes of the NF-κB signaling pathway in ILC1s were examined in the different groups.For the in vivo studies,miR-142-3p-Agomir was injected in the uterus of abortive mice to evaluate the abortion rate and alterations of ILC1s at the maternal-fetal interface,and further detect the expression of HMGB1,pro-inflammatory cytokines,and the NF-κB signaling pathway.Results The number of ILC1s was significantly increased,the level of HMGB1 was significantly upregulated,and that of miR-142-3p was considerably downregulated in the abortive mice as compared with the normal pregnant mice(all P<0.05).In addition,miR-142-3p was found to drastically inhibit the activation of the NF-κB signaling pathway(P<0.05).The number of ILC1s and the levels of pro-inflammatory cytokines were significantly downregulated and the activation of the NF-κB signaling pathway was inhibited in the miR-142-3p Agomir group(all P<0.05).Conclusion miR-142-3p can regulate ILC1s by targeting HMGB1 via the NF-κB signaling pathway,and attenuate the inflammation at the maternal-fetal interface in abortive mice. 展开更多
关键词 maternal-fetal interface group 1 innate lymphoid cells(ILCis) high mobility group box 1(HMGB1) miR-142-3p ABORTION
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A Diagnostic Analysis of Winter Atmospheric Circulation during the 1982-1983 ENSO Event
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作者 滕星林 符淙斌 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1990年第1期57-66,共10页
In this paper, the winter atmospheric circulation, the convection along the equator and their variations of 1982 and 1983 are investigated. It is suggested that there was a well organized three dimensional structure o... In this paper, the winter atmospheric circulation, the convection along the equator and their variations of 1982 and 1983 are investigated. It is suggested that there was a well organized three dimensional structure of anomalies of the atmospheric circulations during 1982 winter which may be related to the variations of the convection in the equatorial region. 展开更多
关键词 A Diagnostic Analysis of Winter Atmospheric Circulation during the 1982-1983 ENSO event ENSO
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抗磷脂综合征患者血清sVCAM-1、HMGB1与NLRP3炎症小体信号通路与血栓事件的关系
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作者 汪学刚 朱欣如 +2 位作者 吴艳芬 张晓雪 张鹏辉 《海南医学》 CAS 2024年第11期1623-1628,共6页
目的探讨抗磷脂综合征(APS)患者血清可溶性血管细胞黏附分子-1(sVCAM-1)、高迁移率族蛋白B1(HMGB1)与NOD样受体P3(NLRP3)炎症小体信号通路和血栓事件的关系。方法选择2021年6月至2023年6月上海市浦东新区人民医院收治的124例APS患者作为... 目的探讨抗磷脂综合征(APS)患者血清可溶性血管细胞黏附分子-1(sVCAM-1)、高迁移率族蛋白B1(HMGB1)与NOD样受体P3(NLRP3)炎症小体信号通路和血栓事件的关系。方法选择2021年6月至2023年6月上海市浦东新区人民医院收治的124例APS患者作为APS组和67例健康志愿者作为对照组。检测所有受检者的血清sVCAM-1、HMGB1水平、外周血单个核细胞的NLRP3信使核糖核酸(mRNA)和下游炎症因子白细胞介素(IL)-1β、IL-18水平。采用Pearson相关性分析血清sVCAM-1、HMGB1水平与外周血单个核细胞的NLRP3 mRNA表达、IL-1β和IL-18水平的相关性。根据是否发生血栓事件将APS患者分为血栓组(n=32)和非血栓组(n=90)。采用多因素Logistic回归分析APS患者发生血栓事件的影响因素。采用受试者工作特征曲线(ROC)分析sVCAM-1、HMGB1预测APS患者发生血栓事件的价值。结果APS组患者的血清sVCAM-1、HMGB1、IL-1β和IL-18水平以及外周血单个核细胞的NLRP3 mRNA分别为(806.35±204.75)μg/L、(125.42±24.57)μg/L、(13.62±3.09)pg/mL、(16.24±3.72)pg/mL、1.62±0.42,明显高于对照组的(395.12±77.24)μg/L、(35.01±10.30)μg/L、(3.15±0.67)pg/mL、(4.02±1.13)pg/mL、0.85±0.23,差异均有统计学意义(P<0.05);经Pearson相关性分析结果显示,APS组患者的血清sVCAM-1、HMGB1水平与外周血单个核细胞的NLRP3 mRNA以及血清IL-1β和IL-18水平均呈正相关(P<0.05);血栓组患者的血清sVCAM-1、HMGB1水平分别为(915.35±70.28)μg/L、(136.42±10.17)μg/L,明显高于非血栓组的(767.59±61.43)μg/L、(121.51±15.03)μg/L,差异均有统计学意义(P<0.05);经多因素Logistic回归分析结果显示,3个抗体阳性、高水平sVCAM-1、HMGB1是APS患者发生血栓事件的危险因素(P<0.05);经ROC分析结果显示,血清sVCAM-1联合HMGB预测APS患者血栓事件的曲线下面积(AUC)为0.885,高于单独预测(P<0.05)。结论APS患者血清sVCAM-1、HMGB1水平均增高,且与NLRP3及其下游炎症因子水平增加、血栓事件发生有关,NLRP3炎症小体信号通路的激活可能进一步促进血栓形成。 展开更多
关键词 抗磷脂综合征 可溶性血管细胞黏附分子-1 高迁移率族蛋白B1 NOD样受体P3炎症小体 血栓事件
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胶东辽上金矿荆山群U-Pb年代学特征及其记录的多期地质事件
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作者 陈燕平 李增胜 +3 位作者 李旭平 李洪奎 陈妍蓉 孔凡梅 《岩石学报》 SCIE EI CAS CSCD 北大核心 2024年第11期3643-3662,共20页
辽上金矿是近年来在胶东新发现的一类金矿,即黄铁矿碳酸盐脉型金矿。它明显区别于同地区焦家式破碎带蚀变岩型金矿和玲珑式石英脉型金矿,主要赋存于古元古代荆山群和晚侏罗世玲珑二长花岗岩接触带。矿区荆山群岩石的年代学研究,有助于... 辽上金矿是近年来在胶东新发现的一类金矿,即黄铁矿碳酸盐脉型金矿。它明显区别于同地区焦家式破碎带蚀变岩型金矿和玲珑式石英脉型金矿,主要赋存于古元古代荆山群和晚侏罗世玲珑二长花岗岩接触带。矿区荆山群岩石的年代学研究,有助于理解辽上金矿成矿地质背景。在辽上金矿的钻孔岩心中采集5个荆山群样品,分别为黑云变粒岩、碎裂岩、透辉石变粒岩、浅粒岩和透辉石大理岩,这些岩石均遭遇了晚期成矿流体的交代作用,发生了不同程度的碳酸盐化和黄铁矿化。获取的锆石在阴极发光图像中多呈核-边结构,结合LA-ICP-MS锆石U-Pb年龄和原位微量元素特征显示,该地区荆山群变沉积岩系中碎屑锆石主要为岩浆锆石,年龄分布在2.6~2.0Ga之间,对应的年龄主峰为~2.11Ga,次峰为~2.46Ga,其中最年轻的碎屑锆石的207 Pb/206 Pb年龄为2024±33.6Ma,表明沉积物源主要来源于胶东地区出露的太古宙基底和古元古代中期岩浆岩,且沉积时间不早于2.02Ga。由于变质增生边较窄,获取的变质年龄相对较少,其中最古老的一组变质锆石年龄为~1.95Ga,结合碎屑锆石的年龄,推测该地区荆山群岩系的沉积时间介于2.02G~1.95Ga之间的某一时期。这些变质年龄主要分为两阶段,分别为~1.93Ga和~1.84Ga,与胶东地区古元古代经历的高压麻粒岩相峰期变质作用和峰期后近等压降温变质作用发生的时间一致。对碳酸盐透辉石变粒岩样品中磷灰石进行U-Pb定年,获取的变质年龄为252.5±2.4Ma,表明辽上地区荆山群岩系卷入到二叠纪末期华南板块和华北板块俯冲造山过程中。此外,在该样品的锆石中识别出一组热液锆石,年龄为132.4±3.2Ma,早于辽上金矿的主成矿年龄和胶东半岛其他金矿的成矿年龄,代表成矿前的热液活动,表明辽上金矿成矿作用至少持续了~20Myr。 展开更多
关键词 辽上金矿 荆山群 锆石U-Pb定年 磷灰石U-Pb定年 多期地质事件
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BJ-2搏击项群训练与监控系统的应用方法 被引量:3
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作者 李玉刚 刘存忠 +1 位作者 马世坤 李春木 《武汉体育学院学报》 CSSCI 北大核心 2011年第8期65-68,共4页
BJ-2搏击项群训练与监控系统是专门用于对拳击、散打、跆拳道等搏击项目的技术动作进行定量分析与诊断的体育装备,其主要功能有:①获得单击打击力量(F)、打击速度(V)、打击冲量(S)、打击爆发力(P)参数;②获得连击的最大力量(Fm)、连击... BJ-2搏击项群训练与监控系统是专门用于对拳击、散打、跆拳道等搏击项目的技术动作进行定量分析与诊断的体育装备,其主要功能有:①获得单击打击力量(F)、打击速度(V)、打击冲量(S)、打击爆发力(P)参数;②获得连击的最大力量(Fm)、连击的最大速度(Vm)、连击的最大冲量(Sm)、连击的最大爆发力(Pm)参数,同时还可获得连击的力量衰减率(Fμ)、速度衰减率(Vμ)、爆发力衰减率(Pμ)参数以及在设定时间内的打击次数(N);③实现测试参数、曲线可视化与储存功能。 展开更多
关键词 搏击项群 测试系统 击打靶位 运动生物力学
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辽北辽河群碳酸盐岩碳-氧同位素特征及其地质意义 被引量:29
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作者 汤好书 陈衍景 +1 位作者 武广 赖勇 《岩石学报》 SCIE EI CAS CSCD 北大核心 2008年第1期129-138,共10页
辽宁省关门山地区辽河群形成时代限于2.3~1.85Ga之间,辽河群关门山组白云岩的42件样品的δ^(13)C介于3.5~5.9‰之间,具有明显的正异常特征,δ^(18)O值为15.4‰~24.8‰,指示了对Jatulian事件的响应。其中,未遭受后期流体作用的35件样... 辽宁省关门山地区辽河群形成时代限于2.3~1.85Ga之间,辽河群关门山组白云岩的42件样品的δ^(13)C介于3.5~5.9‰之间,具有明显的正异常特征,δ^(18)O值为15.4‰~24.8‰,指示了对Jatulian事件的响应。其中,未遭受后期流体作用的35件样品的δ^(18)O和δ^(13)C明显高于受到流体作用的7件样品,表明流体作用使碳酸盐岩δ^(18)O和δ^(13)C降低。在地质历史中,以2.33~2.06Ga时期的全球性δ^(13)C_(carb)正漂移最强烈,而辽河群强烈的δ^(13)C_(carb)正漂移现象指示辽河群沉积于2.33~2.06Ca之间。 展开更多
关键词 辽河群 δ^18Ocarb δ^13Ccarb正漂移 Jatulian事件 2.3Ga环境灾变
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2006-2013年“医闹”类群体性事件研究论文的调查分析 被引量:7
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作者 李娜 卢青 戎文慧 《中华医学图书情报杂志》 CAS 2014年第5期50-52,80,共4页
目的:通过统计分析"医闹"类群体性事件研究论文,探讨"医闹"类群体性事件的防范对策。方法:选用万方数据知识服务平台和CNKI中国知网,采用文献计量方法,对2006-2013年"医闹"类群体性事件研究论文的年代分... 目的:通过统计分析"医闹"类群体性事件研究论文,探讨"医闹"类群体性事件的防范对策。方法:选用万方数据知识服务平台和CNKI中国知网,采用文献计量方法,对2006-2013年"医闹"类群体性事件研究论文的年代分布、作者所属机构分布、研究主题等进行统计分析。结果:2006-2013年共发表相关研究论文676篇,作者所属机构以医学院校及医疗卫生机构居多,研究内容以医疗纠纷、医患关系、法律建设、"医闹"原因和防范对策居多,研究"第三方"机制和医疗责任保险的论文较少。结论:相关研究取得了一定进展,但尚存在待改进之处。 展开更多
关键词 医闹 医疗纠纷 医患关系 群体性事件 文献计量
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扬子地块西南缘大红山群石榴白云母-长石石英片岩的白云母^(40)Ar-^(39)Ar定年及其地质意义 被引量:18
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作者 杨红 刘福来 +1 位作者 刘平华 王舫 《岩石学报》 SCIE EI CAS CSCD 北大核心 2013年第6期2161-2170,共10页
大红山群是扬子地块西南缘出露的古元古代结晶基底,主要经历了绿片岩相-低角闪岩相变质作用。本研究对大红山群老厂河组变质中酸性岩和变质沉积岩——石榴白云母-长石石英片岩中的白云母进行了40Ar-39Ar测年,得到三个样品的坪年龄和40Ar... 大红山群是扬子地块西南缘出露的古元古代结晶基底,主要经历了绿片岩相-低角闪岩相变质作用。本研究对大红山群老厂河组变质中酸性岩和变质沉积岩——石榴白云母-长石石英片岩中的白云母进行了40Ar-39Ar测年,得到三个样品的坪年龄和40Ar/39Ar等时线年龄结果较统一,坪年龄代表的变质年龄分别为837.7±4.2Ma、839.6±4.2Ma和844.2±4.2Ma。变质沉积岩和变质中酸性岩的变质时代类似,均介于837~845Ma。大红山群变质基性岩中变质锆石的U-Pb定年年龄为849±12Ma(杨红等,2012),40Ar-39Ar测年数据与锆石定年数据相结合,说明大红山群古元古代结晶基底中的火山岩和沉积岩均在新元古代经历了同期变质作用,其主期低角闪岩相变质作用发生于新元古代837~850Ma。结合前人发表的扬子西缘~750Ma的变质年龄,扬子西缘从北向南的区域变质作用时限可扩展到750~850Ma。此外,扬子西缘存在750~850Ma的岩浆事件,本文研究结果说明,扬子地块西缘在新元古代不仅发生了大规模岩浆作用,也发生了750~850Ma的区域变质作用,扬子西缘存在新元古代的岩浆-变质事件。岩浆事件与变质事件之间可能存在相关性,即新元古代岩浆作用引起了扬子西缘的区域动力热流变质作用。 展开更多
关键词 扬子西缘 大红山群 白云母Ar-Ar定年 新远古代变质事件
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内蒙古西部狼山地区晚古生代变质事件的厘定及其地质意义——来自乌拉山岩群LA-ICP-MS锆石U-Pb定年的新证据 被引量:4
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作者 刘平华 邹雷 +2 位作者 田忠华 冀磊 施建荣 《地质通报》 CAS CSCD 北大核心 2019年第10期1691-1710,共20页
乌拉山岩群是狼山地区最重要的前寒武纪变质基底之一,准确测定其原岩成岩与变质时代,对于进一步探讨狼山地区前寒武纪地质演化具有重要的意义。对狼山地区乌拉山岩群角闪黑云斜长片麻岩及其伴生的花岗质浅色脉体进行了岩石学和锆石U-Pb... 乌拉山岩群是狼山地区最重要的前寒武纪变质基底之一,准确测定其原岩成岩与变质时代,对于进一步探讨狼山地区前寒武纪地质演化具有重要的意义。对狼山地区乌拉山岩群角闪黑云斜长片麻岩及其伴生的花岗质浅色脉体进行了岩石学和锆石U-Pb年代学研究。碎屑锆石U-Pb定年和野外地质调查表明,狼山地区乌拉山岩群角闪黑云斜长片麻岩碎屑锆石年龄介于2591~1800Ma之间,其中最小一组碎屑锆石年龄为1873Ma,结合其约270Ma的变质年龄,初步限定乌拉山岩群角闪黑云斜长片麻岩的原岩沉积年龄为1873~270Ma。综合新的研究资料,认为狼山地区乌拉山岩群除存在新太古代—古元古代变质岩外,可能还存在中元古代—晚古生代变沉积岩。锆石阴极发光图像与U-Pb定年结果综合表明,角闪黑云斜长片麻岩中发育大量变质锆石,获得的206Pb/238U年龄加权平均值为269±4Ma,代表狼山地区乌拉山岩群遭受晚古生代末期角闪岩相变质作用的时代,可能与华北板块与西伯利亚板块晚古生代末期碰撞造山作用有关。此外,采用预剥蚀方法,在乌拉山岩群高硅花岗质浅色脉体高U锆石中,获得的206Pb/238U年龄加权平均值为264±3Ma,被解释为乌拉山岩群花岗质浅色脉体的形成时代,代表本区晚古生代造山作用由同碰撞挤压向碰撞后伸展转换的时限。 展开更多
关键词 狼山 乌拉山岩群 晚古生代变质事件 锆石U-PB定年
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